The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Nano-components and/or micro-components (e.g., particles having diameters between 10 nm and less than a few millimeters) are of increasing interest because of their potential applications as drug delivery systems, sensors, micro-reactors, combined imaging and therapeutics (“theranostics”), or food packaging materials, by way of non-limiting example. In particular, environmentally responsive particles, such as pH-responsive core-shell particles are desirable for their ability to produce custom-tailored release profiles. A series of conventional methods have been used to prepare core-shell particles including emulsion polymerization, layer-by-layer (LbL) adsorption onto solid particles, templated polymerization and template-assisted electropolymerization. However, such conventional fabrication methods tend to be expensive, time intensive, and typically require immiscible solutions, thus compositionally limiting the components formed.
In certain aspects, the present disclosure provides a method of controlling the morphology of a micro-component or nano-component formed via electrohydrodynamic formation techniques enabling a wide variety of composition via relatively facile formation of micro-components. The disclosure provides for the preparation of core-shell components or particles with well-defined structure (e.g., phase alignment) by a side-by-side co-jetting of polymer solutions. In accordance with the present disclosure, a series of methods can be used to prepare core-shell particles, using a layer-by-layer approach, pH-sensitive core-shell particles as well as hollow capsules can be prepared. Another approach to pH-sensitive core-shell particles is the assembly of macromolecules, which display pH-responsive properties, and undergo biodegradation.